Support multiple build configurations

[abroekhuis]

Currently the CMake files don't do anything specific for different build configs. To be able to have release and debug libraries next to each other the following is needed:

• Add postfix: "d" // this somewhat seems to be the standard
• Check if al custom functions work

@pnoltes What else could go wrong? First test seems to be ok for most things (tests and bundle files as well as the executables).

[pnoltes]

We have to do some work for the exported bundles target.

The following part:

#export targets
install(EXPORT celix NAMESPACE Celix:: DESTINATION share/celix/cmake FILE Targets.cmake COMPONENT cmake)
install_celix_targets(celix NAMESPACE Celix:: DESTINATION share/celix/cmake FILE CelixTargets.cmake COMPONENT cmake)

Generates a Targets.cmake and (if I am correct) a Targets-<CMAKE_BUILD_TYPE>.cmake. So this supports multiple build configurations.
The celix command now only generated a CelixTargets.cmake, no CelixTargets-<CMAKE_BUILD_TYPE>.cmake.
This should also be addressed -> mimic behaviour of install(EXPORT ...)

[abroekhuis]

This raises another question, currently a debug build works, all libraries are postfixed with "d", and manifest files and configurations are correct.
But, resulting bundles don't have a debug prefix. So that also means that the CelixTargets.cmake works as it is.
However, I can also think of situations where we want to be able to release bundles for debug, release, etc.
I thinks this adds the following to the list:

• Add postfix to bundle names
  This then also requires an update to the CelixTargets, to actually have a debug and release version.

[abroekhuis]

Also, doing some tests, when doing an install with Debug, and next with Release, libraries are kept, resulting in release and debug libs next to each other.
However.. the install(EXPORT ..) stuff is not kept. For Debug a Targets and Targets-Debug is installed. Running the Release install removed those 2 files, and places back a Targets and Targets-Release.
Not sure yet how to prevent this. IMO we want both files (or multiple, depending on build types) next to each other. The Targets file itself is the same for different build types.

[pnoltes]

Also, doing some tests, when doing an install with Debug, and next with Release, libraries are kept, resulting in release and debug libs next to each other.
However.. the install(EXPORT ..) stuff is not kept. For Debug a Targets and Targets-Debug is installed. Running the Release install removed those 2 files, and places back a Targets and Targets-Release.
Not sure yet how to prevent this. IMO we want both files (or multiple, depending on build types) next to each other. The Targets file itself is the same for different build types.

I also expected that both files were kept.. strange.

[abroekhuis]

When both configurations are the same, the Targets-* files are kept. So that makes sense.

Additional question, what types of builds do we want to install? I think the following makes sense:

• Only use a postfix for the libraries for Debug
• Always use build type as postfix for bundles, except when it is release (not sure about this one)
• Always use build type as postfix for CelixTargets file

For the second one (bundle files), it might also make sense to only use a postfix for Debug, or the other way around, always use a postfix. Since the Targets files already supplies a simplified name for usage in a build.

Do we have an example on how the Targets files are being used?

[pnoltes]

When both configurations are the same, the Targets-* files are kept. So that makes sense.

Additional question, what types of builds do we want to install? I think the following makes sense:

• Only use a postfix for the libraries for Debug
• Always use build type as postfix for bundles, except when it is release (not sure about this one)
• Always use build type as postfix for CelixTargets file

For the second one (bundle files), it might also make sense to only use a postfix for Debug, or the other way around, always use a postfix. Since the Targets files already supplies a simplified name for usage in a build.

I would prefer bundles with a postfix, with exception for the Release or RelWithDebInfo build type.
For the celix targets cmake file, always generate a generic one (without postfix) and one with postfix. The generic will expect and include (based on its own location) a celix targets file with a build type postfix.
So maybe it could be as simple as:

include(CelixTargets-${CMAKE_BUILD_TYPE}.cmake)

Do we have an example on how the Targets files are being used?
See cmake/CelixConfig.cmake line 33

[abroekhuis]

When both configurations are the same, the Targets-* files are kept. So that makes sense.
Additional question, what types of builds do we want to install? I think the following makes sense:

• Only use a postfix for the libraries for Debug
• Always use build type as postfix for bundles, except when it is release (not sure about this one)
• Always use build type as postfix for CelixTargets file

For the second one (bundle files), it might also make sense to only use a postfix for Debug, or the other way around, always use a postfix. Since the Targets files already supplies a simplified name for usage in a build.

I would prefer bundles with a postfix, with exception for the Release or RelWithDebInfo build type.
For the celix targets cmake file, always generate a generic one (without postfix) and one with postfix. The generic will expect and include (based on its own location) a celix targets file with a build type postfix.
So maybe it could be as simple as:

include(CelixTargets-${CMAKE_BUILD_TYPE}.cmake)

Can we not simply generate the different build type files, and use the CelixConfig.cmake to do this?

[abroekhuis]

I've updated the Config to use the proper CelixTargets.

What could be a confusing thing, now all bundles always have a postfix, also for project using Celix. Is this something we want?

Internally I'm fine with it, since with CMake, cmake takes care of using the proper bundle filename etc. But I can imagine this is different for other users.

[pnoltes]

I've updated the Config to use the proper CelixTargets.

What could be a confusing thing, now all bundles always have a postfix, also for project using Celix. Is this something we want?

Internally I'm fine with it, since with CMake, cmake takes care of using the proper bundle filename etc. But I can imagine this is different for other users.

This can create some integration issues for user who use file paths instead of CMake target, but IMO this is an easy fix. So I am also fine with this.

[pnoltes]

This issues is addressed and merged in master